Phonograph reproducer



.Fam'l 1924 c. E. SEMPLE, JR

PHONOGRAPH REPRODUCER im. 15, 1924. y 1,480,7s

C. E. SEMPLE, JR

PHONOGRAPH REPRODUCER Filed May 24, 1922 3 sheets-sheet 2 aEAem/le, c?,

MTA/5555."

Jan, 15, 1924. 1,480,786

c. E. SEMPLE, JR

PHONOGRAPH REPRODUGER Filed May 24. 1.922 SIShee'LS-Sheeb 5 IIIA.

A lunI l y gnu-Mdo? aemjale, 1,7 1-.3

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Patented .lam 15, 1924.

CHARLES E. SEMPLE, J R.

, 0F YOUNGSTOWN, OHIO.

PHONDGRAPH REPRODUC'ER.

Application filed May 24,

To all whom it may concern.'

Be it known that l, CHARLES E. SEMPLE, J r., citizen of the UnitedStates, residing at Youngstown, in the county of Mahoning and State ofOhio, have invented certain new and useful Improvements in PhonographReproducers, of which the following is a specification.

This invention relates to reproducers for phonotgraphs andthe like, andhas particuar re erence to a novel stylus bar construction and mounting,and instrumentalities associated therewith, for effecting an improvedoperating relation between the stylus ar and the diaphragm as well as animproved operation of the diaphragm itself.

A primary object of the invention is to provide a novel stylus barmounting which is extremely sensitive, avoiding to a great extentforeign sounds, blasts and the like, thereby greatly enhancing thecharacter of the reproduction. In this connection the invention proposesa stylus bar co-ordinated with the diaphragm in such a manner as to holdthese two elements in tension relation without subjecting the diaphragmto undue strain, or impeding or hindering the free action of the stylusbar and connecting parts in their movements. That is to say, it isproposed to provide a. construction wherein the stylus bar and diaphragmare held in unitary relation and in balanced tension, thereby avoidinglooseness of parts, aswell as avoiding undue strain upon the diaphragm.

Another object of the invention is to provide a novel diaphragm controlmeans. This is accomplished throu h suitable sub-diaphragms or washersan pads, which are re tained in proper position in contact with thediaphragm by means of the balanced stylus bar and diaphragmipstrumentalities above mentioned. L

With the above and other objects in view which will more readily appearas the na- -ture of the invention is better understood,

the same consists in the novel construction, combination and arrangementof parts, hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of the invention is shown in theaccompanying drawings, in Which- Figure l is a plan view of a reproducerillustrating the present improvements.

Figure 2-is a cross sectional view.

1922. Serial No. 563,442.

Figure 3 is an enlarged detail elevation of the stylus bar and balancingbar.

Figure 4 is a horizontal sectional view taken on the line 4 4. of Figure3 showing the balancing bar and the link which engages with tliediaphragm.

Figure 5 is a detail view of the connection between the stylus bar andthe link.

Figure 6 is a detail perspective view of the stylus bar.

Figure7 is a detail view-illustrating a combined form of balancing barand tensioning coupling.

Figure 8 is a detail View of a further modified form of balancing barand tensioning coupling.

Figures 9 and l0 are detail views taken at right angles to each otherillustrating a modified bearing for the balancing bar on the diaphragm.

Figure l1 is an enlarged detail View 0f a modified arrangement forconnecting the link with the diaphragm. v

Figure l2 is an enlarged detail sectional view taken at right angles toFigure ll.

Similar reference characters .designate corresponding parts throughoutthe several figures of the drawings.

Heretofore it has been the usual practice to utilize a stylus bar madeof either a hard material such as steel or asofter metal. If made of asoft material, with sufiicient stiliness to convey the sound vibrationsto the diaphragm without loss, it must be quite heavy and thereforecorrespondingly slow in action, usually causing blasting. Also sinceaction and reaction are equal and in opposite directions, the stylus barassumes the character of a small hammer beating on the record, and,obviously, the heavier the hammer the faster thel record is destroyed.

When using a stylus bar of hard material,

and attempting to make it lightl and at the same time suilicientlystrong. some method of stii'ening must be resorted to, such as temperingin the case of steel, or in the case 0f other` materials, the choicemust be a material that is naturally stiff. A hard stylus bar of thischaracter is very vibrantand easily sets up vsympathetic vibrationsgiving off sounds peculiar to the material, which are magnified by thediaphragm and reproduced along with the musical composition therebymaking an unnatural or lforeign sound, which is, of course, notdesirable.

In carrying the present invention into.

effect, I propose to use a stylus bar made of comparatively softmaterial and of special formation in cross-section to add stiffness. Inaddition to providing a novel stylus bar the invention also contem latesa novel relatively flexible mounting t erefor.

Stylus bar mountings may be classified generally into two types. one ofwhich aims to connect the stylus bar more or less rigidly to thediaphragm, while the other class provides a relatively flexibleconnection at this point. In the type of mounting wherein the stylus baris relatively rigidly connected to the diaphragm, there is a tendency todistort the diaphragm thereby setting up therein undesirable partialsand causing additional sounds, which are not on the record, to becreated on the diaphragm and imposed on the composition beingreproduced. Furthermore, stylus mountings of this character arecomparatively stiff in action and tend to prevent the needle fromproperly responding to the sound waves recorded in the record, therebygiving the reproduction a thin and unnatural tone, as well as causingblasting when notes of high frequency or great amplitude areencountered.

The flexible type of connection between the arm and the diaphragm hasheretofore been generally used upon reproducers ,for playing' records ofthe hill and dale, or undulating type. In such reproducers the weight ofthe parts is distributed in such a manner that the stylus point ismaintained in engagement kwith the record while the tail end of thestylus bar, through a connecting link, is kept taut with the diaphragm.Therefore, the'weight of the reproducer is the only means of keeping theloosely hung stylus bar connections and diaphragm in properly engagingrelation. In practice it has been found that the weight of thereproducer alone is not sufficient to hold the stylus bar in closeoperating relation with the diaphragm at all times, nor is it sufficientto hold the stylus bar fulcrum firmly on its bearing under unusualrequirements imposed in reproducing tones of high frequency or greatamplitude.

Inlorder to overcome the objections incidental to the different types ofstylus bar, and the different types of mountings therefor, the presentinvention contemplates a novel construction and mounting which willconnect the stylus bar and diaphragm in unitary relation with eachother, while at the same time permitting the necessary freedom of actionat all points of oscillation and also without imposing undue strains onthe diaphram'due to' the tensioning of the stylus bar. l

Accordingly, by reference to the accompanying drawings it will beAobserved that the present device includes in its organization a stylusbar A, a balancing bar B yieldingly connected thereto, a' tensioningcoupling C, and a connecting element L between the stylus bar A and thediaphragm D. While the details of this organization may be changed tomeet manufacturing and other requirements, nevertheless, the generalstructure resulting from the combination 'and arrangement set forthembodies the novel and distinctive features of the present iuvention.

Referring first to the stylus bar A, it will be observed that the sameis preferably of relatively hollow formation, thereby affording not onlythe advantages of light weight but also tending to avoid undesirablelocal vibrations which produce foreign sounds. That is to say, thestylus bar is preferably provided with a head 1 for carrying a styluspoint while the body 2 is of substantially U-shaped or channelformation, the same being preferably made of a comparatively softannealed material. Not only does the shape and material of which the baris made have the effect of deadening cr dampening local vibrations, butalso it conveniently permits of coating the interior of the channel withbeeswax or the like.

Intermediate its ends, the body 2 of the bar A is provided with theoppositely extending knife-edge bearings 3 for engaging in the troughedseats 4 of the support or bridge 5 Vcarried by the frame F of thereproducer. Also, the underside of this bridge 5 is preferably providedwith a knife edge bearing 6 upon which the balancing bar B rests. Thisknife-edge 6 is directly in line with the seats upon which theknife-edges 3 bear so that both the stylus bar A and thc balancing bar Bhave their fulcruming points located on a common center line. And,

to assist in holding the balancing bar B in position, that is to preventundue shifting or accidental displacement, the said bridge I5 is.provided `at one side of the knifeedge 6 with a pin 7 which projectsthrough a flared opening 8 inthe balancing bar B, as clearly shown inFigures 2 andl 3 of the drawings. The object of providing the flaringopening 8 is to further reduce friction and for the same reason the saidpinv 7 is offset to one side of the knife edge. As

will be observed from Figure 4 the end 9 of the balancing bar B may bemade in the form of a loop adapted to bear `upon the diaphragm D, aswill hereinafter more fully appear, while the opposite \end 10 isconnected by the tensioning coupling member C with the head of thestylus bar A.

' `This tensioning coupling member C con-` stitutes one of the novelfeatures of the invention` and is preferably made in the form of aspring loop or eye, formed of fiat spring steel, one leg o of wh'chengages the end 10 of the balancing bar B While the other leg c2connects with the hook 11 at the head 1 of the stylus bar A. When thetensioning coupling member C is thus engaged,ithas a tendency to drawthe head 1 of the/stylus i bar and the end of the balancing bar B towardeach other, thereby forcing the opposite or tail ends of these members.This relatively opposite movement of the tail ends of these membersco-ordinate to equalize the tension exerted upon the diaphragm D throughthe link L. That is to say, the tendency of the stylus-bar A to move inone direction is communicated to the diaphragm D through the link L,While the tendency of end 9 of the balancing bar B to move in theopposite direction causes it to bear against the central part of thediaphragm, as clearly shown in Figures 1, 2 and 4 of the drawings.

The link Ii for connecting the stylus bar with the diaphragm preferablyconsists of a shank portion 13 having a loop or eye 14 at one endthereof for receiving the T-head 15 formed at the tail end of the stylusbar A, and, as will be observed from Figure 5. the said loop or eye ispreferably of elongated formation to permit of the said T-head beinginserted therein and then rotated 90 so that the end of the link yandthe end of the stylus bar may be readily and quickly interlocked. Thisnovel type of interlock prevents possibility of accidental disengagementand yet at the same time allows the main stylus and link to be perfectlyfree to perform their intended functions. To fury ther reduce frictionat the point of connection. the edge of the eye or loop 14 whichcontacts with the stylus bar is preferably formed with a knife edge 16.

The opposite end of the shank 13 of the link L is preferably fo-rmedwith an enlarged head or button 17 which has a relatively swivelingengagement with a hard washer 18 at the inside Aof the diaphragm D.Also, to prevent the setting up of local vibrations in the link L, theshank portion 13 thereof may be fitted with a tubular covering 19.

Obviously, any suitable and practical form of diaphragm D may be used inconnection with the present stylus bar mounting connection, but onepreferred type that is particularly adapted for coordination with thenovel instriunentalities herein described is shown in the drawings, and,for the purpose of fully explaining the functioning and operation of theinvention, reference will now be made thereto. In the embodiment shownin Figure 2. the diaphragm structure D preferably consists of a maindiaphragm plate 20 having a cork ring 21 secured to the face thereof.while within the said ring 21 is arranged a ring 22 of felt or the likeupon which rests a bearing or stitfening member in the form of washer 23preferably of the same material as the diaphragm 20. On top of thissub-washer a pad 24 may be placed as a cushion bearing for the end'oflthe effect of the action of the Stylus bar in transmitting the vibrationto the diaphragm.

By reason of the comparatively large central area covered by theabsorbing and stabilizing members, together with the rigid formation ofthe diaphragm platel 20, the tendency of the diaphragm to vibrate inpartials and causing sounds arising therefrom, which are foreign to therecorded sound, is materially reduced. In other words, the arrangementshown causes the diaphragm to move more as a whole than in partials.

`When using diaphragms other `than the form shown in Figure 2, it shouldbe pointed out that washers 18, 18a, 22 and 23 may necessarily requirechanges in their size and form in order to better overcome theaforementioned tendency of the diaphragm to vibrate in parta-ls.

From the foregoing it will be apparent that the primary novel anddistinctive features of the. invention are a stylus bar and a balancingbar yieldingly connected thereto, which. together with the connectingelements, exert pressure on the opposite side of the diaphragm, therebymaintaining the stylus connections as well as the diaphragm in tension,avoiding looseness, providing a very sensitive constructlon and rehevmgthe diaphragm of distorting tension or stress,

and also at the same time permitting the use of padding means, as forexample pads 18@l and 22. or padded Washers or bearing members 18 and23, in combination for controlling or modifying the tendency of thediaphragm to vibrate in partials.

In the above connection it may be noted that the present invention notonly contemplates the coordinating of the stylus and the diaphragm, ashereinbefore illustrated and described, but also contemplates combiningwith the main diaphragm suitable bearing members 18 and 23 for example,in such manner as the conditions may require. In Figure 2, as well as inFigures 7 to 10 inclusive, it will be observed that the so-calledbearing members 18 and 23, which may take substantially the form ofWashers of the same material as the diaphragm\ 20, are spaced from thediaphragm by means of the felt pads or washers 18a and 22. It is pointedout that the felt pads are not adhesively secured to the diaphragm, butloosely bear thereon so that they will not flex or bend the handling ofthe reproducer, the outer face of the bridge or support 5 is providedwith a guard G which overlies and protects these elements as at G and G2in Figure 1.

To provide the necessary clearance for the stylus point carried by thehead 1 of the stylus bar A, the body of the guard has an opening G3,while the lateral extensions G2 permit of the guardbeing attached to thebridge by means of screws or equivalent fasteners. r l

`By way of illustrating the range of modification which may be resortedto in carrying the invention into effect, reference may be made toFigures 7 to 12 inclusive of the drawings, which show several practicaldetails of modifications.

Referring first to Figure`7, it will be observed that the stylus bar Amay be used in connection with a combined balancing bar and tensioningcoupling B2. In this embodiment the bar B2 is preferably made ofresilient metal, the body portion B3 of which is formed in substantiallythe same manner as the balancing bar B, as heretofore described,

while the end opposite the one bearing against the diaphragm is formedinto a spring loop portion B4. Thus, the balancing bar and tensioningmeans may be an integral member according to this embodiment of theinvention.

A further modification is shown in Figure 8 wherein the stylus bar A isused in conjunction with a bar B5 the end B6 of which bears against thediaphragm in the manner already described, while the end B'l connectswith a straight tensioning coupling C3. The tensnioning coupling C3 maybe of an elastic or yielding material in event that the balancing bar Biis made of more or less rigid material; or, on the other hand, if thebar B5 is made of resilient material, it may be placed under tension byusing a straight piece of wire orthe like for the coupling C3. In thelatter event the inelastic coupling C2 would, of course, be relativelshort so as to maintain the yielding or exible bar B5 .relatively bowedand under tension at all times.

Figures 9 and 10 of the drawings illustrate a modified form of bearingfor the balancing bar B on the diaphragm. As previously indicated,a'certain amount of longitudinal movement of the balancing bar B maytake place, and in the construction shown in Figures 1 and 2 that isprovided by the soft pad 24. However, if it is desired to furtherreduc-e friction at this point a knife edge bearing member 26 may beused. This member may consist of the knife edge portions 27 connected bya web 28, and respectively bearing against the underside of the bar Band the upper side of the hard washer fw. By this arrangement, frictionat this point is reduced and at the same time provision made for thelongitudinal movement of the bar B.

y To further assist in clarifying the tone by increasing thesensitiveness of the connection between the 'link and the diaphragm atthe inner side of the latter, the construction shown in Figures 11 and12 may be utilized. As will be observed from the figures referred to,the link L may be provided with a loop L" at its upper end for receivinga knife edge member L8 adapted to bear against the hard washer to2 whichrests upon the pad 18", or the like. .This construction provides for alimited area of contact between the link and the diaphragm and makesthis type of connection very sensitive. However, in using this form ofconnection it is necessaryA to provide means for preventing an air leakat this point, and to that end a small conical cap 29 is glued orotherwise secured to the washer 102.

It will, of course, be understood that other modifications may beadopted in carrying the invention into effect, but the foregoing is toillustrate certainv of the most practical modifications which have beenfound efiicient in practice. f Y

Without further description it is thought that the features andadvantages of the invention will be readily apparent to those skilled inthe art and it will, of course, be understood that changes in the form,proportion and minor details of construction .v may be resorted towithin the -scope of the appended claims.

I claim:

1. A sound reproducer including a diaphragm, a stylus bar operativelyconnected with' the diaphragm, and a second bar having a tensioningconnection with the stylus bar and engaging with the diaphragm andnormally neutralizing .the tens1on imposed on the diaphragm by thestylus bar.

'2. A sound reproducer ofthe class described, lincluding a diaphragm, -astylus bar, a balancing bar.I means for connecting said diaphragm tosaid stylus bar, and means for connecting said diaphragm and said stylusbar with said balancing bar in such a manner as to hold said diaphragmand saidstylus bar in tensioned relation, substantially as described.

, stylus bar and the balancing bar are drawn toward each other to placethe same under tension.

4. A sound reproducer of the class described including a diaphragm, astylus bar connected with the diaphragm, and means for impartingopposing tensioning forces to the diaphragm and stylus bar.

5. A sound reproducer of the class described including a diaphragm, astylus bar flexibly connected with the diaphragm, and means engagingwith the diaphragm and with the stylus bar for placing the two undertension and relieving the diaphragm from -undue strain.

6. A sound reproducer of the class described including a diaphragm, astylus bar flexibly connected with the diaphragm, and a balancing barconnected with the stylus bar and also bearing on the diaphragm adjacentthe point where the4 stylus bar connects therewith.

7. A sound' reproducer of the class described including a diaphragm, a.stylus bar flexibly connected with the diaphragm, and a balancing baryieldingly connected with the stylus bar and bearing against thediaphragm adjacent the point where the stylus bar connects therewith.

8. A Isound reproducer of the class described including a diaphragm, astylus bar flexibly connected with the diaphragm, and a balancing bar,one end of which is yieldingly connected to the stylus bar while theoppositevend bears against the diaphragm adjacent the point where thestylus bar connects therewith.

9. A sound reproducer of the class described including a diaphragm, astylus bar fulcrumed intermediate its ends, means for flexiblyconnecting the bar and the diaphragm, and a balancing bar fulcrumed inline with the stylus bar and having one end bearing against thediaphragm, and an elastic connection between the balancing bar and thestylus bar.

10. A sound reproducer of the class described, including a diaphragm, asupport arranged at one side of the diaphragm, a stylus bar fulcrumed insaid support, a connection between the stylus bar and the diaphragm, abalancing bar also fulcrumed on said support and having one end bearingagainst the diaphragm and a tensioning coupling connecting the oppositeend of the balancing bar with the stylus bar.

11. A sound reproducer of the class described, including a diaphragm, asupport arranged at one side of the diaphragm and having a. knife edge,a stylus bar having knife-edge bearings resting on said support, aconnection between one end of the stylus bar and the diaphragm, abalancing bar fulcrumed on the knife edge of the support and having oneend bearing against` the diaphragm. and a tensioning coupling memberconnecting the other end of the balancing bar with the stylus bar.

12. A sound reproducer of the class described, including a diaphragm,stylus and balancing bars fulcrumed intermediate their ends and having'a tensioning connection at one end, a link for connecting the stylus barwith the diaphragm, and a knife edge device interposed between the endof the balancing bar and the diaphragm.

13. A sound reproducer of the class described, including a diaphragm, astylus bar having a substantially T-shaped end portion, a link having anelongated eye for receiving the T-head portion of the stylus bar andinterlocking therewith.

14. A sound reproducer of the class described, including a diaphragm, astylus bar having a substantially T-shaped end portion, and a linkhaving a relatively elongated eye, one side of which is provided with aknife edge, said-eye being adapted to receive the T-head of the stylusbar whereby when the T-head is turned 90 it will be interlocked with theeye and the knife edge of the latter will bear on the shank of the saidT-head.

15. A sound reproducer of the class described, including a diaphragm,bearing members at opposite sides of the diaphragm, a stylus barflexibly connected indirectly with the diaphragm through one of saidbearing members, and a balancing bar yieldingly connected with thestylus bar and bearing indirectly against the opposite face of thediaphragm through the other of said bearing members.

16. A sound reproducer of the class described, including a diaphragm,padded washers at opposite sides of the diaphragm, a stylus bar flexiblyconnected indirectly with the diaphragm through one of the paddedwashers, and a balancing bar yieldingly connected with the stylus barand bearing indirectly against the opposite face 'of the diaphragmthrough the other of said padded washe '17. A sound reproducer of theclass described including a diaphragm, a pair of padded washers havingAtheir padded sides in contact withopposite faces of the diaphragm, asupport arranged at one side of the diaphragm, a stylus bar fulcrumed 1nsaid support, a connection between the stylus bar and one of said paddedwashers, a balancing bar also fulcrumed on said support and having oneend bearing against the other washer and a tensioning couplingconnecting the opposite endsl of the balancing bar and the stylus bar.

18. A sound reproducer of the class described including a diaphragm, apair of padded washers having their padded faces disposed on oppositefaces of said diaphragm and in contact therewith, a stylus bar, abalancing bar, a tensioning means, means for connecting one of saidwashers to said stylus bar, means for connecting the other washer withsaid balancing bar, the tensioning means being so disposed between thestylus bar and the balancing bar as to hold said diaphragm 'firmlyclamped between said padded washers substantially as described.

-19. A sound reproducer of the class described including a diaphragm,pads loosely mounted thereon, a tensioned balancing constructionincluding tensioned members one of which isa stylus bar exertingopposing forces on opposite sides of the diaphragm and serving to clampsaid pads to the diaphragm.

20. A sound reproducer of the class described including a diaphragm, apair of padded washers having their padded sides iii-contact withopposite faces of the diaphragm, a support arranged at one side of thediaphragm, a stylus bar fulcrumed in said su port, a connection betweenthe stylus bar ang one of said padded washers, a `balancing bar alsofulcrumed on said support and having a knife edge bearing deviceinterposed between one end of said balancing bar and the other washerand a tensioning coupling connecting the opposite ends of the balancingbarand the stylus bar.

21. A sound reproducer of the class described including a maindiaphragm, a stylus bar having tensioning connections exerting opposingforces against opposite sides of the diaphragm, and bearingmembers in,contact with the opposite faces of the main diaphragm and held inposition thereon by means of said tensioned connections.

In testimony whereof I hereunto afiix my signature in the presence oftwo witnesses.

CHARLES E. SEMPLE, JR.

Witnesses:

LnrLA C. AUGUSTIN-E, NABEL SczEmNcK.

